U.S. patent application number 15/553631 was filed with the patent office on 2018-02-15 for filter device.
The applicant listed for this patent is RT-FILTERTECHNIK GMBH. Invention is credited to Marco BAUTZ, Gerhard STEHLE.
Application Number | 20180043290 15/553631 |
Document ID | / |
Family ID | 55809067 |
Filed Date | 2018-02-15 |
United States Patent
Application |
20180043290 |
Kind Code |
A1 |
BAUTZ; Marco ; et
al. |
February 15, 2018 |
FILTER DEVICE
Abstract
A filter device, having a support part (39, 43) and a filter
part (1) that can be received therein, having at least one sealing
device (17) that acts between the support part (39, 43) and the
filter part (1), and having a securing device (53, 57, 61) for
releasably connecting the support part (43) to the filter part (1),
which securing device has a circumferential collar part (53) and,
under the action of at least one energy store (61), exerts a force
on the sealing device (17), which force seals the support part (39,
43) and the filter part (1) in a fluid-tight manner with respect to
one another, wherein the support part (39, 43) has, at least on its
end region oriented toward the securing device (53, 57, 61),
another circumferential collar part (39), is characterized in that
the collar part (53) of the securing device (53, 57, 61) is guided
concentrically within the collar part (39) of the support part (39,
43) which is provided with a sealing system (41, 72).
Inventors: |
BAUTZ; Marco;
(Friedrichshafen, DE) ; STEHLE; Gerhard;
(Konstanz, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
RT-FILTERTECHNIK GMBH |
Friedrichshafen |
|
DE |
|
|
Family ID: |
55809067 |
Appl. No.: |
15/553631 |
Filed: |
April 19, 2016 |
PCT Filed: |
April 19, 2016 |
PCT NO: |
PCT/EP2016/000631 |
371 Date: |
August 25, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B01D 2201/4053 20130101;
B01D 29/58 20130101; B01D 2201/122 20130101; B01D 29/232 20130101;
B01D 2201/4015 20130101; B01D 29/21 20130101; B01D 35/0276
20130101; B01D 35/147 20130101; B01D 2201/291 20130101; B01D
2201/342 20130101 |
International
Class: |
B01D 29/23 20060101
B01D029/23; B01D 29/58 20060101 B01D029/58; B01D 29/21 20060101
B01D029/21; B01D 35/027 20060101 B01D035/027; B01D 35/147 20060101
B01D035/147 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 9, 2015 |
DE |
10 2015 007 691.4 |
Claims
1. A filter device having a support part (39, 43) and a filter part
(1) capable of being received therein, having at least one sealing
mechanism (15, 17) that acts between the support part (39, 43) and
the filter part (1), and also having a securing mechanism (53, 57,
61) for releasably connecting the support part (43) to the filter
part (1), which securing mechanism has a circumferential collar
part (53) and which under the action of at least one energy store
(61) exerts a force on the sealing mechanism (15, 17), which force
seals the support part (39, 43) and the filter part (1) in a
fluid-tight manner with respect to each other, wherein the support
part (39, 43) has, at least on its end region facing the securing
mechanism (53, 57, 61), another circumferential collar part (39),
characterized in that the collar part (53) of the securing
mechanism (53, 57, 61) is guided concentrically within the collar
part (39) of the support part (39, 43), which is provided with a
sealing system (41, 72).
2. The filter device according to claim 1, characterized in that in
the filtration mode of said device, the energy store (61) applies
the collar part (53) of the securing mechanism (53, 57, 61) with
settable sealing force against a sealing element (15) of the
adjacently arranged one end cap (5) of the filter part (1).
3. The filter device according to claim 1, characterized in that
this one end cap (5) moves the other end cap (3) of the filter part
(1) via the filter medium (7), under the action of the energy store
(61), against the sealing mechanism (17) that acts between the
support part (39, 43) and the filter part (1), resulting in an
increased effect of the sealing force.
4. The filter device according to claim 1, characterized in that
the action of the energy store (61) of the securing mechanism (53,
57, 61) is transferred via the sealing mechanism (17) between the
filter part (1) and the support part (39, 43) onto the collar part
(39) of the support part (39, 43), which abuts with at least parts
(41) of its sealing system (41, 72) on housing parts (37) of a
receiving housing (25) for the support part (39, 43) and the filter
part (1) together with the securing mechanism (53, 57, 61),
resulting in an increased effect of the sealing force.
5. The filter device according to claim 1, characterized in that
the sealing mechanism (17) that acts between the support part (39,
43) and the filter part (1) is arranged, in particular molded, on
the other end cap (3) of the filter part (1), which other end cap
presses on an adjacently arranged end cap (71) of the support part
(39, 43) under the action of the energy store (61) of the securing
mechanism (53, 57, 61).
6. The filter device according to claim 1, characterized in that
the collar part (39) of the support part (39, 43) is graduated and
that the inwardly folded, in particular inwardly crimped end (44)
of a perforated support tube (43) of the support part (39, 43)
rests on a step (66) of this collar part (39).
7. The filter device according to claim 1, characterized in that
the collar part (39) of the support part (39, 43) is provided, on
its inner circumference, with another sealing mechanism (72)
serving as part of the sealing system (41, 72), on which the collar
part (53) of the securing mechanism (53, 57, 61) that is graduated
correspondingly to the collar part (39) of the support part (39,
43) rests in a sealing manner.
8. The filter device according to claim 1, characterized in that,
in the filtering mode and with all sealing mechanisms (15, 17, 41,
72) exerting a sealing effect, when viewed in the axial direction
parallel to the longitudinal axis of the filter device, there is
essentially a virtually force-free contact between each of the
correspondingly graduated inner wall surfaces (66, 68) of the two
collar parts (39, 53), which are guided concentrically into one
another.
9. The filter device according to claim 1, characterized in that
the collar part (53) of the securing mechanism (53, 57, 61) has
outwardly oriented latching bolts (74) projecting above its upper
rim which, as the securing mechanism (53, 57, 61) is twisted with
respect to the support part (39, 43), can be brought into lateral
engagement with assignable latching hooks (65) of the other collar
part (39), of which the axial extension is dimensioned in such a
way that the latching bolts (74) in engagement with the latching
hooks (65), guided in a contact-free manner under the action of the
energy store (61), execute an axial, force-transferring feed motion
on the sealing mechanism (15) of the one upper end cap (5) of the
filter part (1).
10. The filter device according to claim 1, characterized in that
the collar part (39) of the support part (39, 43) has, at least
partially adjacent to the free opening of the latching hooks (65),
a control cam (63) provided with a ramp-like rise to facilitate the
disengagement of the filter part (1) from the support part (39,
43).
11. A tank device having a tubular housing part (25), into which a
filter device according to the configuration of features of claim 1
can be inserted via a housing opening that can be closed with a
tank lid (32), which lid exerts a force on a compression spring
(61) of a securing mechanism (53, 57, 61) of the filter device in
such a way that the filter device is sealingly received in the
tubular housing part (25).
Description
[0001] The invention relates to a filter device, having a support
part and filter part that can be received therein, having at least
one sealing mechanism that acts between the support part and the
filter part, and having a securing mechanism for releasably
connecting the support part to the filter part, which securing
mechanism has a circumferential collar part and which, under the
action of at least one energy store, exerts a force on the sealing
mechanism that seals the support part and the filter part in a
fluid tight manner with respect to one another, wherein the support
part has, at least on its end region oriented toward the securing
mechanism, another circumferential collar part.
[0002] A filter device of this generic type is disclosed in
Document EP 0874 675 B1. For generating the force that acts on the
sealing mechanism, the securing mechanism in this prior art filter
device has a tie rod that passes from the open end of the filter
element, coaxially to the longitudinal axis of the device, entirely
through the filter part and the support part, wherein on the free
end of the tie rod that passes through the associated end cap, a
first energy store is provided that pulls the support part against
a collar part of the securing mechanism, which is in turn secured
on the outer housing of the device by means of a second energy
store. The operational safety of this device leaves much to be
desired for several reasons. For one thing, the transfer of the
spring force of the first energy store to the end surface of the
end cap, even if the latter is made of metal, is critical because
of the deformation risk resulting from the increased sealing force.
For another thing, it is difficult to seal the place where the tie
rod passes through. Furthermore, if the long tie rod is pulled
diagonally, there is a risk of the entire support part tilting,
resulting in a correspondingly non-uniform transfer of force to the
collar part of the securing mechanism, resulting in a
correspondingly compromised sealing.
[0003] On the basis of this prior art, the object of the invention
is that of providing a filter device of the aforementioned generic
type, which is distinguished by improved operating performance,
particularly in terms of improved sealing.
[0004] According to the invention, this object is achieved by means
of a filter device that has the features of claim 1 in its
entirety.
[0005] According to the characterizing part of claim 1, an
essential feature of the invention lies in the fact that the collar
part of the securing mechanism is guided concentrically within the
collar part of the support part, which is provided with a sealing
system. Because an axial guide is formed in this manner for the
component that directly transfers the sealing force, an optimum
transfer of the force acting in the axial direction to the filter
part is guaranteed, thus in turn assuring optimum sealing.
[0006] The arrangement can be advantageously made such that in the
filtering mode of the device, the energy store applies the collar
part of the securing mechanism with a presettable sealing force
against a sealing element of the adjacently arranged one end cap of
the filter part. A second energy store such as the one required in
the aforementioned prior art solution for securing the collar part
of the securing mechanism to the device housing thus becomes
superfluous.
[0007] In particularly advantageous exemplary embodiments, the one
end cap allocated to the collar parts moves the other end cap of
the filter part, via the filter medium under the action of the
energy store, against the sealing mechanism that acts between the
support part and the filter part, resulting in an increased effect
of the sealing force. As a result, the force generated by the only
energy store present is applied as a sealing force on both end
caps.
[0008] Furthermore, the arrangement can advantageously be made such
that the action of the energy store of the securing mechanism is
transferred via the sealing mechanism between the filter part and
the support part to the collar part of the support part, which
abuts with at least parts of its sealing system on housing parts of
a receiving housing for the support part and the filter part
together with the securing mechanism, resulting in an increased
effect of the sealing force. Thus not only are the support part and
the filter part kept under sealing contact force by the force of
the energy store, but by means of the energy store the composite
formed from these parts is also secured in the device housing
concerned.
[0009] In particularly advantageous exemplary embodiments, the
sealing mechanism that acts between the support part and the filter
part is arranged, in particular molded, on the other end cap of the
filter part, and this sealing mechanism presses on an adjacently
arranged end cap of the support part under the action of the energy
store of the securing mechanism.
[0010] The arrangement can be made particularly advantageously such
that the collar part of the support part is graduated and such that
the inwardly folded, in particular inwardly crimped, end of a
perforated support tube of the support part rests on a step of this
collar part. A positive fit is thus formed in a simple manner,
which secures the collar part against being lifted from the support
part.
[0011] With particular advantage, the collar part of the support
part can be provided, on its inner circumference, with another
sealing mechanism as part of the sealing system, against which the
collar part of the securing mechanism, which is graduated in a
manner corresponding to the collar part of the support part, rests
in sealing contact.
[0012] In a particularly advantageous manner, the geometry in the
area of the graduated surface sections of the two collar parts can
be dimensioned such that, in the filtering mode of the device and
with all sealing mechanisms exerting a sealing effect, when viewed
in the axial direction parallel to the longitudinal axis of the
filter device there is essentially a virtually force-free contact
between each of the correspondingly graduated inner wall surfaces
of the two collar parts, which are guided concentrically into each
other. A clearance for a relative axial movement between the collar
parts is thus provided for transferring the sealing force supplied
by the energy store and acting on the collar part of the securing
mechanism to each of the downstream sealing mechanisms for forming
seals between the securing part, the filter part, and the support
part.
[0013] In particularly advantageous exemplary embodiments, the
collar part of the securing mechanism has outwardly oriented
latching bolts projecting above its upper edge which, as the
securing mechanism is twisted with respect to the support part, can
be brought into lateral engagement with assignable latching hooks
of the other collar part, wherein the axial extension thereof is
dimensioned in such a way that the latching bolts in engagement
with the latching hooks are guided in a contact-free manner. With a
latching mechanism thus configured and consisting of the latching
bolts and latching hooks, an axial clearance necessary for the
transfer of force onto the sealing system is still available even
with the latching bolts and latching hooks in the engaged
state.
[0014] In particularly advantageous exemplary embodiments, the
collar part of the support part has, at least partly adjacent to
the free opening of the latching hooks, a control cam, which is
provided with a ramp-like rise to facilitate the disengagement of
the filter part from the support part. To this end, the cam ramps
allocated to a given latching bolt can be arranged and formed in
such a way that as the securing mechanism is twisted, an axial
motion component via which the two collar parts are moved apart in
the axial direction is imparted to the latching bolts.
[0015] According to claim 11, a tank device having a tubular
housing part, into which a filter device according to the
configuration of features of one of claims 1 through 10 can be
inserted via a housing opening, is also the subject matter of the
invention.
[0016] In the following, the invention is explained in detail with
reference to an exemplary embodiment depicted in the drawings.
[0017] FIG. 1 shows an illustration of an exemplary embodiment of
the filter device according to the invention, in a perspective
oblique view and cut longitudinally;
[0018] FIG. 2 shows a partial longitudinal section of just the
lower end region of the filter device, drawn to a larger scale
relative to FIG. 1 and in a perspective oblique view;
[0019] FIG. 3 shows a partial longitudinal section of just the
upper end region of the exemplary embodiment of the filter device,
drawn to the scale of FIG. 2 and in a perspective oblique view;
[0020] FIG. 4 shows a detail of the area designated by IV in FIG.
3, magnified in relation to FIG. 3;
[0021] FIG. 5. shows an incomplete perspective oblique view of the
area of the collar parts of the support part and of the securing
mechanism of the device; and
[0022] FIGS. 6-8 show views corresponding to FIG. 5, in which
different movement phases of the securing mechanism during the
release of the connection between the collar parts are
depicted.
[0023] With reference to the drawings, the filter device of the
invention is explained using a so-called in-tank filter device as
an example, which receives a filter element 1 in a relatively
thin-walled, circular cylinder-shaped filter housing 25, which has
on its upper end a flange part 27, with which it is secured on an
upper tank opening (not illustrated) in such a way that the lower
open end 29 of the housing 25 extends into the tank concerned up to
a height that lies below the operating fluid level. On the upper
end, the housing 25 can be closed with a lid 32 screwed to the
flange part 27. At a short distance from the flange part 27, a
supply pipe 31 opens into the housing 25 via an inlet opening
33.
[0024] As can be clearly discerned in FIGS. 2 and 3, the filter
element 1 has a lower end cap 3 and an upper end cap 5. As FIG. 2
shows most clearly for the end cap 3, the end caps 3, 5 form the
enclosure for a given end of a filter material 7 that forms a
hollow cylinder, which in this example has the form of a folded
mesh pack. Both end caps 3 and 5 have a circular outer rim 9, on
which the outside of the filter material 7 rests in the example
shown. However, the filter material 7 does not necessarily have to
rest on a rim of the end caps 3, 5. Whereas the upper end cap 5
likewise has a circular inner rim 11, the lower end cap 3 has an
inner rim 13 in the shape of a polygon, namely a Reuleaux triangle
in the example shown. The non-circular connection area on the end
cap 3 can be used to form a so-called safeguard against incorrect
installation, as a matching non-circular geometry is provided for
the connection area provided on the filter device for the end cap
3, thus assuring that the fluid coupling connection between the
filter element and the filter device can only be made if the
geometries of the right filter element 1 and the connection area of
the end cap 3 match.
[0025] Both end caps 3 and 5 each have a circumferential seal 17
and 15, respectively, which seals are molded from an elastic
material onto the rigid material that forms the end caps 3, 5. As
FIG. 3 shows, the seal 15 for the upper end cap 5 is molded in such
a way that it forms an axial sealing surface 19, which is
configured as sloping down via an inclined plane 21 towards the
outer circumference of the upper [sic] end cap 3. The seal 17 of
the lower end cap 3 is molded in such a way that at least one
radial sealing edge 23 is formed. As can be discerned in FIGS. 2
and 3, which illustrate the situation with the filter element 1
being installed in the filter device, the sealing surfaces 19 and
23 are used to form seals on the securing parts, by means of which
the filter element 1 can be positioned in the filter device of the
invention.
[0026] Below the inlet opening 33, an inward crimp 35 is formed in
the wall of the filter housing 25, which inward crimp is shaped in
such a way that a sort of step or flank 37 is formed on a radially
recessed area (FIG. 3), on which a collar part (which has the shape
of a graduated annular body 39) of the support part of the device
is braced by a seal 41 against downward axial movement. As shown in
FIG. 3, the graduated annular body 39, which forms the collar part
of the support part of the device, is connected to a perforated
support tube 43 of the support part. The support tube 43, on which
rests the outside of the filter material 7 of the filter element 1,
extends to the lower open end of the filter housing 25. As FIG. 2
shows, an inward crimp 45 is provided on the lower end of the
support tube 43, by means of which a rigid bottom part 47 is
connected to the support tube 43. In combination with the annular
body 39 and the bottom part 47, the support tube 43 serving as a
component of the support part thus forms a sort of inner housing
for the filter element 1, which can be inserted from above. As the
filter element 1 is being inserted, i.e., moved axially downward
from the partially inserted position shown in FIG. 2, the bottom
part 47, together with a bypass valve housing 49 connected thereto,
forms a lower securing part for the lower end cap of the filter
element 1.
[0027] As already indicated, in order to form a sort of key/lock
system, the outer circumference of the bypass valve housing 49 has
a polygonal shape in the contact or sealing area 51 that
corresponds to the Reuleaux triangle on the inner rim 13 of the end
cap 3, see FIG. 2. If the polygonal shapes of the inner rim 13 of
the end cap 3 and the outer circumference of the bypass valve
housing 49 that forms the sealing area 51 serving as the lower
securing part of the filter device do not match, the filter element
1 cannot be moved into the engaged functional position. An
effective fail-safe mechanism is thus formed that prevents an
improper filter element 1 that is not suited for the intended use
from being put into operation.
[0028] As another collar part which is associated with the securing
mechanism and by means of which the filter element 1 is kept in the
installed functional position on the lower securing part, i.e. the
bottom part 47 with the bypass valve housing 49, a retaining ring
53 is provided that engages in the graduated inner circumference of
the annular body 39 that forms the collar part of the support part,
which retaining ring has a graduated shape corresponding to the
inside of the annular body 39 and which, in its functional
position, rests with its inner, lower end rim 55 on the sealing
surface 19 of the end cap 5. One-piece bars 57 extend radially
inwardly in an upwardly inclined manner from the inside of the
retaining ring 53 to a centrally located spring bearing 59
supporting a compression spring 61, the other end of which rests in
contact on the housing lid 32 and thus exerts a downward axial
pretensioning force on the retaining ring 53 and generates the
sealing force with which the end rim 55 rests in contact on the
sealing surface 19 of the end cap 5.
[0029] As already mentioned, the support tube 43, in combination
with the bottom part 47 connected thereto on the lower end by means
of the inward crimp 45, forms an inner housing for the filter
element 1, wherein the bottom part 47 forms a securing part for the
filter part. As can best be discerned from FIG. 4, the upper end of
the support tube 43 has an outwardly angled rim 44, which rests on
a step 66 on the inside of the annular body 39 serving as a collar
part of the support part. The inner housing formed by the support
tube 43 is thus braced against the sealing force generated by the
compression spring 61, which is transferred from the end rim 55 of
the retaining ring 53 to the upper end cap 5 and via the filter
element 1 to the lower end cap 3, and from the latter in turn to
the bottom part 47 serving as the lower securing part, on the
annular body 39, whereby the latter is in turn secured in a sealing
manner via the ring seal 41 on the recessed flank 37 of the filter
housing 25. In order to assure an unobstructed transfer of the
sealing force from the retaining ring 53 serving as a collar part
of the securing part to the upper end cap 5, the dimensions of the
retaining ring 53 and the annular body 39 serving as a collar part
of the support part, as well as the position of the steps 66, 68
formed thereon, are selected in such a way that in the installation
state, as shown most clearly in FIG. 4, there is an axial clearance
between the step 66 on the annular body 39 and the opposite step 68
on the retaining ring 53, which serves as space for a relative
axial movement. In the area adjoining the steps 66, 68 in an
axially downward direction, there is likewise a radial clearance 70
between the annular body 39 and the retaining ring 53. A suitable
guide, on which a ring seal 72 forms the sealing area, is formed
only in the area adjoining the steps 66, 68 in the upward direction
between the annular body 39 and the retaining ring 53. The sealing
force generated by the compression spring 61 thus acts via the
filter element 1 as an axial force, which is transferred from the
upper rim 44 of the support tube 43 to the annular body 39 and via
the latter in turn to the ring seal 41, which rests on the flank 37
of the housing 25.
[0030] As can be discerned most clearly from FIGS. 5-8, provision
is made of a plurality of cam tracks 63 on the upper
circumferential rim of the annular body 39, to each of which is
attached a latching hook 65 extending above the end of the
associated cam track 63 in the circumferential direction. To
interact with these latching hooks 65, radially outwardly
projecting latching bolts 74 are provided on the upper rim of the
retaining ring 53 that forms the collar part of the securing
mechanism. FIG. 5 shows the installed state, in which the sealing
force generated by the compression spring 61 is effective. The
latching bolts 74 are at the lowest point of the cam tracks 63
under the hooks 65, although there is still an axial clearance
between the latching bolts 74 and the given cam track 63 so that
the elastic force of the compression spring 61 is not exerted by
the latching bolts 74 on the retaining ring 53, which is secured in
the axial direction on the flank 67 of the housing 25, but instead
is exerted without obstruction on the annular body 39, which is
decoupled from the retaining ring 53 in terms of axial movements by
the clearance that exists between the steps 66 and 68.
[0031] If the housing lid 32 is loosened, the compression spring 61
is decompressed so that the securing mechanism can be removed
without any tension, for example in order to take the filter
element 1 out of the inner housing of the support part in order to
change it. In order to keep the support part, i.e. the inner
housing with the support tube 43 plus the annular body 39 forming
its collar part, in the housing 25, the retaining ring 53 and the
annular body 39 must be moved apart axially. This can be effected
in an expedient manner by turning the latching bolts 74 clockwise
by means of a clockwise rotary movement of the bars 57 with the
retaining ring 53, wherein the latching bolts are forcibly actuated
in axially upward movement along the cam tracks 63 and a relative
axial movement takes place between the retaining ring 53 and the
annular body 39. It is furthermore possible to effect the rotary
movement by means of a tool such as a ratchet wrench, which engages
on a hex head to which the spring 61 is also coupled. The
sequential movement phases of this rotary movement are shown in
FIGS. 6 and 7. Any friction acting between these collar parts 39,
53 in the guide zone sealed by means of the seal 72 is thus
overcome in an expedient manner. The cam tracks 63 and the latching
bolts 74 interact in this way to form an aid for dismantling the
filter element 1. The entire securing mechanism 53, 57, 61 along
with a permanent magnetic bar 69, which is mounted on the spring
bearing 59 and which extends therefrom in the axial direction into
the interior of the filter element 1, can thus be removed in an
expedient manner (cf. FIG. 8).
[0032] As can be discerned most clearly in FIG. 2, the lower end
cap 3 has an inner body in the shape of a dome 71, which starting
from the polygonally-running inner rim 13, extends axially into the
interior filter cavity and has a ring of fluid openings 73 on its
upper end. On the inside, the dome 71 forms a fillet 75 that
extends in the axial direction by means of a recessed wall region.
The bypass valve housing 49, which extends into the dome 71 when
the filter element 1 is in its inserted operating position, has an
external shape that corresponds to the internal shape of the dome
71 and has on its outside a channel-like wall recess 77, which
forms a sliding surface 79 (see FIG. 2), along which the fillet 75
of the dome 71 is guided when the filter element 1 is pushed
downwards from the starting position shown in FIG. 2 and into the
operating position. The fillet 75, in combination with the sliding
surface 79 on the recess 77 of the bypass valve housing 49, thus
forms a rotary positioning mechanism, which aligns the polygon on
the inner rim 13 of the end cap 3 congruently to the polygonal
shape on the sealing area 51 of the bypass valve housing 49. The
latter forms, on the inner rim 81 of an upper housing opening 83, a
valve seat for the seating of a valve body 85 of the bypass valve.
The valve body 85 is pretensioned by a valve spring 87, which is
mounted on a connecting piece 89 located on the bottom part 47.
With the filter element 1 installed, the outer wall of the valve
housing 49 furthermore forms the sealing seat in conjunction with
the lower ring seal 17 having a circumferential sealing edge 23 of
the lower end cap 3.
[0033] With the filter element 1 in the filtration mode in the
illustrated in-tank filter device, the fluid flows through the
inlet opening 33 on the front side of the filter element 1 and
reaches the inner filter cavity that forms the crude or
non-filtrate side through the opening on the inner rim 11 of the
end cap 5. After flowing through the filter material 7 from the
inside to the outside to the clean or filtrate side in the space
between the support tube 43 and the housing wall 25, the filtrate
exits into the tank via the open lower end of the housing 25.
Obviously, the filter element 1 cannot only be advantageously used
with an in-tank filter device, but with all types of filter devices
in which corresponding securing parts are provided for connections
to end caps, the filter elements of which are shaped in a special
non-circular manner.
[0034] Although a Reuleaux polygon is shown here, in which the
polygonal shape is located on the lower end cap 3 and the
connection area of the upper end cap 5 is circular cylindrical,
both end caps 3 and 5 could each be provided with a different
polygonal shape, or the lower end cap 3 could have a circular
cylindrical connection geometry and the polygonal shape could be
provided on the upper end cap 5. The polygonal connection geometry
could be provided on an outer rim of one or both end caps or on the
inner rim of one end cap and on the outer rim of the other end cap,
rather than on the inner rim 13 of the end cap 3 as in the present
example. Furthermore, use could be made of end caps having
characteristic polygonal shapes that differ from one another.
* * * * *